If you’ve kept up with memes in the past few years, then you know that young people on the internet are obsessed with serotonin, a neurotransmitter that’s supposed to make us happy. But a recent large-scale review of several studies found that depression actually might not be caused by low levels of serotonin, a pretty damning conclusion when you consider that several modern antidepressants — known as SSRIs, or selective serotonin reuptake inhibitors — focus solely on increasing the levels of that exact chemical in our brain.
The review, published in the journal Molecular Psychiatry, was conducted by researchers at University College London who analyzed 17 existing studies and found no clear evidence linking low serotonin levels to depression, per New Scientist. Among those 17 studies was one in which life circumstances turned out to be a very strong driver of depression, and another in which participants’s serotonin levels were artificially lowered but did not cause depression in people who didn’t already have it, according to The Guardian. Instead, researchers concluded that serotonin is likely just one small piece of a larger puzzle, and depression is likely caused by a variety of factors, including genetics and physical environment.
